Related Stories

Flightless bird Ostrich-like dinosaurs roamed the Earth millions of years ago using feathers to attract a mate or protect offspring rather than for flight, according to a new study.

Researchers from the Royal Tyrrell Museum of Palaeontology, and the University of Calgary made the discovery in the 75-million-year-old rocks in the badlands of southern Alberta.

The ostrich-like dinosaurs, known as ornithomimids, were thought to be hairless, fleet-footed birds and were depicted as such in the Hollywood movie Jurassic Park.

But the researchers found evidence of feathers with a juvenile and two adult skeletons of ornithomimus, a species within the ornithomimid group.

The fossils were discovered in sandstone and were the first feathered dinosaur specimens found in North America, according to the museum. Until now feathered dinosaurs have been found mostly in China and in Germany.

"This is a really exciting discovery, as it represents the first feathered dinosaur specimens found in the Western Hemisphere," says Darla Zelenitsky, an assistant professor at the University of Calgary and lead author of the study published today in the journal Science.

She says the find "suggests that all ornithomimid dinosaurs would have had feathers."

According to the researchers the specimens also reveal that the dinosaurs boasted a base of down-like feathers throughout their lifetime while older ones developed feathers on their arms, approximating wings.

Francois Therrien, curator at the Royal Tyrrell Museum in Drumheller, Alberta and the co-author of the study says the dinosaurs would have been too large to fly.

"The fact that wing-like forelimbs developed in more mature individuals suggests they were used only later in life, perhaps associated with reproductive behaviours like display or egg brooding," he says.